There is known a differential transmission system that allocates a differential signal pair, comprising signals having opposite phases, to two signal lines forming a pair. Since the differential transmission system has a feature that a high data transfer rate can be achieved, it has recently been put to practical use in various fields. In the case of using the differential transmission system, a differential signal connector is used for connecting lines adapted to transmit differential signals. The differential signal connector has a connector fitting side for fitting to a mating connector and a board soldering side for connection to a board of a device or a liquid crystal display.
This type of connector is disclosed in JP-A-2008-41656 and has a plurality of signal pins and a plurality of ground pins. Allocation of these signal pins and ground pins will be described with reference to FIGS. 9 and 10. In FIGS. 9 and 10, S+ represents a signal pin allocated with a positive phase signal of differential signals, S− represents a signal pin allocated with a negative phase signal of differential signals, and G represents a ground pin allocated with ground. In the following description, each signal pin may also be referred to as S without discrimination.
Referring to FIG. 9, on the connector fitting side 1, signal pins S+, signals pins S−, and ground pins G are arranged in a single row. Specifically, (GSSG) is allocated to a left end and then (SSG) is repeatedly allocated.
On the other hand, on the board soldering side 2, signal pins S+, signals pins S−, and ground pins G are, as a whole, staggered in two rows. Specifically, (GSSG) is allocated to a left end of the upper row in the figure and then (SSG) is repeatedly allocated while only (SGS) is repeatedly allocated to the lower row in the figure.
Referring to FIG. 10, on the board soldering side 2, signal pins S+, signals pins S−, and ground pins G are, as a whole, staggered in two rows. Specifically, (GSSG) is allocated to a left end of the upper row on the board soldering side 2 in the figure and then (SSG) is repeatedly allocated while a dummy pin or a ground pin is allocated to a left end of the lower row on the board soldering side 2 in the figure and then pins are allocated in the same manner as in the upper row.